input text文本框内部最后面放一个按钮

.ContSpan
        {
            border: 1px solid #;
            display: inline-block;
        }
        .ContSpan span
        {
            cursor: pointer;
            background: url("/image/add.png") no-repeat scroll 1px 3px transparent;
            cursor: pointer;
            display: inline-block;
            height: 20px;
            opacity: 0.6;
            overflow: hidden;
            vertical-align: top;
            width: 18px;
        }
        .ContSpan input
        {
            border: none;
            width: 128px;
        }
        .spFocus //鼠标放上去 改变透明度
        {
            opacity: ;
        }

　　　　　　　　　　　　　　　　　　<span class="ContSpan">
                                <input type="text" isck="ck" id="txtpayment" readonly="readonly" />
                                <span id="payment" attrid="payment" attrname="change" title="选择"></span>
                            </span>

效果图：

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